JCU > Research Portfolio > Dr Alexandra Roberts

About

Alex uses genetic, proteomic and metabolomic approaches to study both infectious and chronic diseases.

She is currently funded by a Queensland Accelerate Fellowship to characterise the virulence mechanisms of the chytrid fungus Batrachochytrium dendrobatidis, a pathogen that has caused massive population declines in frog species worldwide. Alex is also funded by a JCU Rising Star Grant to study how oxidative stress can drive obesity-linked liver cancer.

Her previous research has focused on thiol-dependent antibiotic resistance and oxidative stress protection in Firmicutes, iron sequestration in marine actinomycetes, and the biosynthesis of cyanobacterial toxins.

Teaching

BC2013: Principles of Biochemistry (Level 2; TSV)
BC2014: Principles of Biochemistry for Pharmacy Students (Level 2; TSV)
BC5102: Advanced Molecular Basis of Disease (Level 5; TSV)
BC5312: Research and Dissertation in Molecular and Cell Biology (Level 5; TSV)
BM1000: Introductory Biochemistry and Microbiology (Level 1; TSV)
TV1102: Cell Biology and Biochemistry for Veterinary Science and Agriculture (Level 1; TSV)

Interests

Research

Enzymology
Virulence mechanisms
Amphibian chytrid fungus
Chytridiomycosis
Liver cancer
Metabolomics
Oxidative stress

Experience

2018 to present - Lecturer - Molecular and Cell Biology, James Cook University (Townsville, Australia)
2013 to present - Research Fellow, James Cook University (Townsville, Australia)
2010 to 2012 - Senior Research Associate, University of East Anglia (Norwich, UK)
2008 to 2010 - Postdoctoral Researcher, Scripps Institution of Oceanography at University of California San Diego (San Diego, USA)
2004 to 2009 - PhD Microbiology and Immunology, University of New South Wales (Sydney, Australia)

Research Disciplines

Socio-Economic Objectives

Honours

Fellowships

2015 to 2018 - Accelerate Fellowship - Department of Science, Information Technology, Innovation and the Arts
2016 to 2017 - Rising Star Grant - James Cook University
2004 to 2008 - Australian Postgraduate Award
2004 to 2008 - CRC for Water Quality and Treatment Postgraduate Award

Memberships

2016 - Member of the Australian Society for Microbiology
2016 - Member of the Australian Society for Biochemistry and Molecular Biology

Publications

These are the most recent publications associated with this author. To see a detailed profile of all publications stored at JCU, visit ResearchOnline@JCU. Hover over Altmetrics badges to see social impact.

Journal Articles

Roberts A, Berger L, Robertson S, Webb R, Kosch T, McFadden M, Skerratt L, Glass B, Motti C and Brannelly L (in press) The efficacy and pharmacokinetics of terbinafine against the frog-killing fungus (Batrachochytrium dendrobatidis). Medical Mycology,
Brannelly L, Roberts A, Skerratt L and Berger L (2017) Epidermal cell death in frogs with chytridiomycosis. PeerJ, 5. pp. 1-20
Scheele B, Skerratt L, Grogan L, Hunter D, Clemann N, McFadden M, Newell D, Hoskin C, Gillespie G, Heard G, Brannelly L, Roberts A and Berger L (2017) After the epidemic: ongoing declines, stabilizations and recoveries inamphibians afflicted by chytridiomycosis. Biological Conservation, 206. pp. 37-46
Berger L, Roberts A, Voyles J, Longcore J, Murray K and Skerratt L (2016) History and recent progress on chytridiomycosis in amphibians. Fungal Ecology, 19. pp. 89-99
Wang W, He Y, Yu G, Li B, Sexton D, Wileman T, Roberts A, Hamilton C, Liu R, Chao Y, Shan Y and Bao Y (2015) Sulforaphane protects the liver against CdSe quantum dot-induced cytotoxicity. PLoS ONE, 10 (9). pp. 1-17
Gaballa A, Chi B, Roberts A, Becher D, Hamilton C, Antelmann H and Helmann J (2014) Redox regulation in Bacillus subtilis: the bacilliredoxins BrxA(YphP) and BrxB(YqiW) function in de-bacillithiolation of S-bacillithiolated OhrR and MetE. Antioxidants & Redox Signaling, 21 (3). pp. 357-367
Luan H, Meng N, Fu J, Chen X, Xu X, Feng Q, Jiang H, Dai J, Yuan X, Lu Y, Roberts A, Luo X, Chen M, Xu S, Li J, Hamilton C, Fang C and Wang J (2014) Genome-wide transcriptome and antioxidant analyses on gamma-irradiated phases of Deinococcus Radiodurans R1. PLoS ONE, 9 (1). pp. 1-11
Posada A, Kolar S, Dusi R, Francois P, Roberts A, Hamilton C, Liu G and Cheung A (2014) Importance of bacillithiol in the oxidative stress response of Staphylococcus aureus. Infection and Immunity, 82 (1). pp. 316-332
Chi B, Roberts A, Huyen T, Bäsell K, Becher D, Albrecht D, Hamilton C and Antelmann H (2013) S-bacillithiolation protects conserved and essential proteins against hypochlorite stress in Firmicutes bacteria. Antioxidants & Redox Signaling, 18 (11). pp. 1273-1295
Fang Z, Roberts A, Weidman K, Sharma S, Claiborne A, Hamilton C and Dos Santos P (2013) Cross functionalities of Bacillus deacetylases involved in bacillithiol biosynthesis and bacillithiol-S-conjugate detoxification pathways. Biochemical Journal, 454 (2). pp. 239-247
Rajkarnikar A, Strankman A, Duran S, Vargas D, Roberts A, Barretto K, Upton H, Hamilton C and Rawat M (2013) Analysis of mutants disrupted in bacillithiol metabolism in Staphylococcus aureus. Biochemical and Biophysical Research Communications, 436 (2). pp. 128-133
Roberts A, Sharma S, Strankman A, Duran S, Rawat M and Hamilton C (2013) Mechanistic studies of FosB: a divalent-metal-dependent bacillithiol-S-transferase that mediates fosfomycin resistance in Staphylococcus aureus. Biochemical Journal, 451 (1). pp. 69-79

More: ResearchOnline@JCU stores 20+ research outputs authored by Dr Alexandra Roberts from 2007 onwards.

Current Funding

Current and recent Research Funding to JCU is shown by funding source and project.

Morris Animal Foundation - Pilot Studies

Reducing fungal virulence via RNAi

Indicative Funding: $13,800
Summary: This project aims to mitigate the effect of fungal diseases via small interfering RNA (siRNA) using Batrachochytrium dendrobatidis (Bd) infection in amphibians as a model system. Bd produces metabolites that suppress frog immunity, therefore, siRNAs will be developed to inhibit immunosuppressant production and improve host survival. First, siRNAs will be transfected into the pathogen, to confirm gene silencing and determine the effect on growth and virulence. Effective siRNAs will then be tested in vivo by spraying topically onto infected frogs, to improve disease resistance.
Investigators: Alexandra Roberts in collaboration with Lee Berger, Rebecca Webb and Lee Skerratt (College of Public Health and Medical & Vet Sciences)
Keywords: Amphibian Declines; Virulence; Antifungal treatment; Chytrid

Australian Wildlife Society - University Student Grant

The role of serotonin in frog host response to chytridiomycosis

Indicative Funding: $1,500
Summary: Frog populations in Australia and globally have declined dramatically due to the spread of the amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd). It is important to understand how some frogs are able to resist Bd so that managers can use this knowledge to better protect threatened species. The goals of my project 1. to investigate molecules in frog skin that fight Bd infection and 2. To examine if antioxidants are involved in Bd's ability to evade the host defences.
Investigators: Sieara Claytor, Lee Berger, Alexandra Roberts and Lee Skerratt (College of Public Health and Medical & Vet Sciences)
Keywords: Amphibian disease; Batrachochytrium dendrobatidis; Virulence; Metabolites; Mycology; Microbiology

Wet Tropics Management Authority - Student Research Grant Scheme

Controlling chytridiomycosis: Characterising virulence factors from the frog-killing fungus Batrachochytrium dendrobatidis

Indicative Funding: $1,500
Summary: My research project aims to reduce the impacts of this invasive pathogen. By understanding how compounds produced by frog skin improve host resistance, I hope to develop targeted treatments that may be applied to wild or captive frogs, and produce information that could inform selective breeding programmes of highly endangered species. These programmes exist for several species in NSW and Victoria, as with the southern corroboree frog (Pseudophryne corroboree), and are being developed for Queensland species, such as the Kroombit Tinkerfrog (Taudactylus pleione). In the Wet Tropics, L. lorica only persists as two small isolated populations in drier forest that is inhospitable to Bd, whereas it previously mostly inhabited rainforest. Unless its innate resistance to infection can be improved, it will not be capable of recolonising the rainforest where Bd is thriving.
Investigators: Sieara Claytor, Lee Berger, Alexandra Roberts and Lee Skerratt (College of Public Health and Medical & Vet Sciences)
Keywords: Amphibian Disease; Virulence; Metabolites; Mycology; Microbiology; Batrachochytrium dendrobatidis

Department of Innovation, Tourism Industry Development and the Commonwealth Games - Accelerate Fellowships

How the fungus kills the frog: Determining the mechanisms of chytrid virulence

Indicative Funding: $180,000 over 3 years, in partnership with Taronga Conservation Society Australia ($30,000 over 2 yrs)
Summary: The fungal disease chytridiomycosis has caused global extinctions of amphibians, including six Australian frog species ? all of them from Queensland. Five more Queensland frog species are endangered and two are critically endangered. These species will likely become extinct unless intensive management strategies for chytridiomycosis are implemented. The causative fungus (Batrachochytrium dendrobatidis) inhibits the frog immune system and damages the skin, leading to death via cardiac arrest. However, the lack of understanding of how the fungus causes these effects has undermined effective disease management. To address this problem, I will firstly identify virulence factors that will enable the development of novel diagnostic screens, to map the distribution of virulent strains in the wild. This approach will identify hotspots of high risk for future disease outbreaks. Secondly, I will develop targeted drugs to overcome immunosuppression and enhance vaccination against the disease. Lastly, viruses of fungi will be investigated to find suitable biocontrol agents that will kill the fungus, and hence, treat infected frogs in captivity and in the wild. Overall, this project will inform management and frog reintroduction practices in Queensland to help control the spread and impact of this devastating disease, and ultimately safeguard our unique amphibian biodiversity.
Investigators: Alexandra Roberts (College of Public Health and Medical & Vet Sciences)
Keywords: Amphibian Chytrid Fungus

QLD Department of Science, Information, Technology and Innovation - Advance Queensland Women's Academic Fund

New Methods To Protect Frogs From Chytridiomycosis

Indicative Funding: $13,000
Summary: Amphibians are under threat from the frog-killing fungus, which causes the fatal skin disease chytridiomycosis. My research investigates new methods to protect captive and wild frogs from chytridiomycosis, including testing new therapeutics and characterising virulence mechanisms of the pathogen. The Advance Queensland Women?s Academic Fund supports women in maintaining their research careers, and supports Queensland Organisations in promoting the achievements of Queensland?s female researchers. The funding can be used to employ a research assistant to continue research progress while on parental leave.
Investigators: Alexandra Roberts, Lee Berger and Richard Webb (College of Public Health and Medical & Vet Sciences)
Keywords: Chytrid Fungus; Amphibian Declines; Antifunal treatments; Molecular Biology

Supervision

Advisory Accreditation: I can be on your Advisory Panel as a Primary or Secondary Advisor.

These Higher Degree Research projects are either current or by students who have completed their studies within the past 5 years at JCU. Linked titles show theses available within ResearchOnline@JCU.

Current

The Role of Fructose in Liver Cancer (PhD , Secondary Advisor)
Reducing Virulence of Fungal Pathogens using Genetics Tools (PhD , Primary Advisor)
Controlling Chytridiomycosis: Characterizing immunosuppressants and mycoviruses from the frog-killing fungus, Batrachochytrium dendrobatidis (PhD , Secondary Advisor)

Collaboration

The map shows research collaborations by institution from the past 7 years.
Note: Map points are indicative of the countries or states that institutions are associated with.